This invention relates to improvements in spa covers with lifting devices and, in particular, to improvements in the types of spa covers and lifting devices disclosed in my U.S. Pat. Nos. 5,974,599, issued Nov. 2, 1999; 6,185,063, issued Dec. 12, 2000; 6,634,036, issued Oct. 21, 2003; and, 6,938,281, issued Sep. 6, 2005.
The foldable spa cover and lifting device of this invention automates the lifting unit of operation and improves the thermal efficiency of the preferred assembly during use.
Spa covers come in a variety of different configurations adapted to conform to the open top of a spa. Typically, a heated spa has a spa structure or housing that supports an insulated spa cover to retain the heat of the spa water during periods of non-use. A conventional spa cover comprises a thick, insulated foam pad covered with a protective, impervious casing. Because the spa cover can become unwieldy, the modern spa cover is typically foldable along a center fold to facilitate removal and replacement. This folding feature of the modern spa cover was used to advantage in the spa cover lifting devices described in the referenced U.S. Pat. Nos. 5,974,599 and 6,158,063. A spa cover lifting device eases the burden of removing and replacing the spa cover by use of a pivoting lifting frame that is connected to the spa structure.
In embodiments prior to the U.S. Pat. No. 6,634,036, the lifting devices had a cross member that spanned the spa cover and took advantage of the fold in the cover to engage the cover when lifting the folded cover to a convenient vertical storage position or returning the folded cover from the storage position to the top of the spa. In such a system the lifting frame had two arms that were pivotally mounted to the spa structure and supported a cross member over the top of the spa cover. Although not fixed to the spa cover, the lifting frame is effectively connected to the cover when the cover is folded over the cross member of the frame. During periods of non-use, when the cover is unfolded and lying flat on the top of the spa structure, the cross member rests on the top of the cover and detracts from the appearance of the cover. In certain instances the weight of the cross member and lifting arms can deform the top of the cover. Additionally, when the spa cover lifting frame is sold as a kit, the frame must be provided with adjustment mechanisms in order to adapt the frame to a particular cover and spa structure.
The integrated spa cover and lifting device described in U.S. Pat. No. 6,634,036 enables the spa cover to be engaged at the sides thereby eliminating the unattractive and potentially damaging cross member. Additionally, with a part of the lifting mechanism incorporated into the cover, an adjustable cross member is not required and the frame parts are reduced in number and cost. These and other features of the improved spa cover and lift unit will become apparent from the following summary and detailed description of the preferred embodiments.